Issue #2914527 by mlncn: Fix check for combination of values must be unique

The combination of values from the specified fields must be unique option did not work, though the code to make it work was partially there. This finishes and fixes that.

Related to #2914527

unique_field.module

@@ -290,8 +290,6 @@ function unique_field_form_validate(array &$form, FormStateInterface $form_state
       $query = \Drupal::database()->select('node_field_data', 'n');
       $query->fields('n', ['nid']);
     }
-    $query = \Drupal::database()->select('node_field_data', 'n');
-    $query->fields('n', ['nid']);
     if ($field_name == 'title') {
       $query->condition('n.title', $title);
     }
@@ -327,8 +325,8 @@ function unique_field_form_validate(array &$form, FormStateInterface $form_state
       }
 
       $col_name = $field_type == 'entity_reference' ? $field_name . '_target_id' : $field_name . $suffix;
-      $query->join($table_name, 'f', 'n.nid = f.entity_id');
-      $query->condition('f.' . $col_name, $field_values, 'IN');
+      $query->join($table_name, $field_name, 'n.nid = ' . $field_name . '.entity_id');
+      $query->condition($col_name, $field_values, 'IN');
 
       if ($scope == 'language') {
         $query->condition('f.langcode', $langcode);
@@ -340,9 +338,24 @@ function unique_field_form_validate(array &$form, FormStateInterface $form_state
     if ($node) {
       $query->condition('n.nid', $node->id(), '<>');
     }
+    if ($comp_type == 'each') {
+      $res = $query->execute()->fetchField();
+      if ($res) {
+        $form_state->setErrorByName($field_name, t('The field @field_label has to be unique.', ['@field_label' => $field_label]));
+        $user = \Drupal::currentUser();
+        if ($user->hasPermission('unique_field_perm_bypass')) {
+          $form_id = str_replace('_', '-', $form['#id']);
+          $msg = t('Your form has unique field validation errors. Click <a href="#" onclick=":onclick">here</a> to bypass this check and resubmit.', [':onclick' => "jQuery('form#" . $form_id . " input[name=\'unique_field_override\']').val(1);jQuery('form#" . $form_id . "').submit();return false;"]);
+          \Drupal::messenger()->addWarning($msg);
+        }
+        $form_state->setRebuild();
+      }
+    }
+  }
+  if ($comp_type == 'all') {
     $res = $query->execute()->fetchField();
     if ($res) {
-      $form_state->setErrorByName($field_name, t('The field @field_label has to be unique.', ['@field_label' => $field_label]));
+      $form_state->setErrorByName($field_name, t('The combination of fields including @field_label has to be unique.', ['@field_label' => $field_label]));
       $user = \Drupal::currentUser();
       if ($user->hasPermission('unique_field_perm_bypass')) {
         $form_id = str_replace('_', '-', $form['#id']);